Oil derivative



Patented Jan. 14, 1936 UNITED STATES.

on. DERIVATIVE Merlin Martin Brubaker, Wilmington, DeL, as-

signo to E. I. du Pont de Nemours & Company, Wilmington, DeL, acorporation of Delaware No Drawing. Original application April 11, 1932,

' Serial No. 604,666. Divided and this application March 29, 1934,Serial No. 718,088

9 Claims.

v acted with organic polycarboxylic acids in such proportion as to yielda product soluble in organic .solvents, preferably a fluid or' viscousoil at ordinary temperature.

Castor oil consists chiefly (about 85%) of glyceryl triricinoleate whichmay be expressed by the following formula:

Ordinary castor oil is used extensively in ni-.

trocellulose coatings and plastics. However, castor oil turns rancidbecause of oxidation which occurs at the ethylenic double bonds of theglyceryl triricinoleate. When such rancidification occurs, a brittlenessof the py'roxylin film softened with castor oil develops." Removal ofthe double bonds by hydrogenation, which may be effected in 40 the knownmanner by using a nickel catalyst below 200 C., converts the glyceryltriricinoleate to 12-hydroxy stearin, a compound having the followingformula:

IZ-Hydroxy stearin I This product, however, is a hard white wax 55melting at 86 C. and incompatible with nitrocellulose. It cannottherefore, without further modification, be used as a film softeningagent. This material still contains the hydroxyl groups originallypresent in the ricinoleic acid molecule, and I have discovered that whenthese 'hydroxyl groups are esterified with organic polycarboxylic acids,as described herein, liquid to resinous products result which arereadily compatible with nitrocellulose.

I have found that very valuable softening agents for nitrocellulosefilms may be obtained by esterifying hydrogenated castor oil, whichconsists essentially of l2-hydroxy stearin with aromatic or aliphaticdicarboxylic acids in particular, as exemplified by the followingexamples.

By the term "hydrogenated castor oil as used in the presentspecification and claims, is meant that type of hydrogenated productwherein the ester linkages and hydroxyl groups are unaffected and theethylenic double bonds are hydrogenated,

said product consisting essentially of 12-hydroxy stearin.

Example I t A mixture of 700 parts of hydrogenated castor A mixture of700 parts of hydrogenated castor oil and 115 parts of succinic acid isheated with or without stirring or blowing at 225 C. for 8 hours, oruntil the acid number has reached a value of, roughly, 25.0. The productis a very viscous liquid. f It may be used as such without furtherpurification.

Inlike manner the esterificatlon may be conducted with polycarboxylicacids other than those mentioned in Examples I and 11. Other examples ofsuitable polycarboxylic aromatic acids are trimesic, salicyl-acetic,chlorophthalic, trimellitic, naphthalic, quinolinic, and diphenic acids.Further examples of other suitable aliphatic' polycarboxylic acids arecitric, tartaric, fumaric, dilactylic, tricarballyic, and sebacic acids.In general, all polycarboxylic acids 7 whether aliphatic, aromatic, orheterocyclic may be used. I desi'redtto be understood that the termipolycarboxylic acid referred to in the claims includes either the acidor the anhydride thereof.

In certain cases the castor oil, during drastic hydrogenation, losessome of its hydroxyl groups and the resulting hydrogenated productcontains stearin which is not afiected by the esterification processesas illustrated above. The stearin is presumably formed by dehydrationand subsequent hydrogenation of the ethylenic double bond which isformed. If a considerable amount of stearin is present in thehydrogenation product,

it will separate unchanged in the final hydro- ,genated castor oil esteras a white solid. Any stearin which separates from the oily reactionproduct claimed herein may be removed by iiltra-.

tion through filter cloth where the reaction product is of lowviscosity. Where this product is of high viscosity, it may be thinnedwith a solvent, e. g., acetone, in which the reaction product is solubleand the stearinis practically insoluble. The latter can then readily beremoved by filtration and the filtrate heated at 100 C. in vacuo forabout two hours to remove the solvent.

Although these esters are most conveniently prepared by heating thehydrogenated castor oil with the acid, any of the well known methods ofesterific'ation may be used, as for instance by re-- acting thehydrogenated castor oil with an acyl halide or an acid anhydride.Furthermore, the hydrogenated castor oil may be esterified with mixturesof different polycarboxylic acids, or with mixtures of mono andpolybasic acids. The

. esterification may be carried out in the presence of a nonreactivesolvent, as in my co-pending application Serial No. 425,5 85 filedJanuary 17, 1930. In general the reaction may be carried out attemperatures between 150 and 275 C. but it is preferred to operate at210-250 C. Furthermore these esters can be prepared by the hydro-'genation of polycarboxylic acid esters of castor oil which may be donein solution, e. g. in

"Decalinfi if necessary.

' A typical example of a nitrocellulose composition containing myimproved softeners and suitable for use in coating fabrics for thepreparation of artificial leather is as follows:

In these examples the softening agent indicated may be replaced withotherpolycarboxylic acid esters of hydrogenated castor oil, such as thesuccin'ate of Example II.

For use as softeners in films for artificial leather coatings, theesters of aliphatic polycarboxylic acids produce films having relativelyhigh exudaviscosity, lend toughness to thenitrocellulose film.

tion temperatures; While the softening agents produced fromthe aromaticpolycarboxylic acids do not yield films having as high an exudationtemperature as those produced with aliphatic acids, the aromatic acidsdo, however, produce softening agents which, because of their higher Theviscosity and consequent toughening propbe used and different ratios ofsoftener, pyroxylin,

erty increases in general with the number of carboxyl groups, thetricarboxylic acids, for example, being more efi'ective in this respectthan the dicarboxylic acids. In nitrocellulose coatings for artificialleather increase in viscosity is, however, 5 undesirable beyond acertain pointv and the dicarboxylic acids as esterifying agents arepreferred as a' rule.

Mixtures of the various softening agents can pigment and gum may be usedin the coating compositions as will be readily understood by thoseskilled in the art.

The present invention finds its most important use in the preparation ofsuch compositions as 15 are used in the coating of fabrics for theproduction of artificial leather.

As softeners in less flexible lacquers and (mmels such as those used onmetal or wood surfaces, etc., I may use the more viscous products, orcertain of the esters not so desirable in artificial leather coatings.Obviously, many other uses will suggest themselves to those skilled inthe art, such as adhesives, lubricants, fluids for hydaulic shockabsorbers, and impregnating agents for paper, fabric and other porousmaterials.

In many cases it will be found that esterification with polycarboxylicacids, if carried too far. will produce gelled or insoluble products;these are unsuitable for the purposes of the present invention. Thegelation can be avoided by heating at a-lower temperature for a shorterperiod of time, or by including monohydric alcohols and/ ormonocarboxylic acids as additional reaction components.

Films fiowed from nitrocellulm coating compositions containing myimproved softening agents have been found to withstand, after aging,either the same numberofibends, or a greater number than they wouldinitially and no rancid- 4o ity development could be detected afteraging. in

certain of these softeners greater'toughhess and a higher-exudationtemperature is imparted to the pyroxylin film. The exudation temperatureofthe film is as great as, and is usually greater 5 than, one in whichcastor oil is the softener.

Although the use of my new esters has been described with particularreference to nitrocellulose, other cellulose derivatives such 'as theacetate, propionate, aceto butyrate, the ethyl or 60 benzyl ethers,etc., may be used with these new products in coating, plastic,impregnating, or adhesive compositions.

As many apparently widely different embodiments of this invention may bemade without departing from the spirit and scope thereof, it is to beunderstood that I do not limit myselfto the specific embodiments thereofexcept as'defined in carboxylic acid and hydrogenated castor oilconsisting essentially of hydroxy stearin.

4. *I'he oily efition product ofaromatic dicar- 7.0 boxylic acid andhydrogenated castor oil consisting essentially of hydroxy stearin.

5 The oily reaction productof phthalic acid and hydrogenated castor oilconsisting essentially of hydroxy stearin.

6. The oily reaction product oi. aliphatic poly- 9. A process formanufacturing a product solcarboxylic acid and hydrogenated castor oilconuble in organic solvents which comprises esterifysisting essentiallyof hydroxy stearin. ing hydrogenated castor oil, in the absence of 7.The oily reaction product of aliphatic dicarsubstantial amount of treepolyhy ic 31601101,

' boxylic acid and hydrogenated castor oil consistwith a polycarboxylicacid, said hydrogenated ing essentially of hydroxy stearin. castor oilconsisting essentially of hydroxy 8. The oily reaction product ofsuccinic acid stearin.

and hydrogenated castor oil consisting essentially MERLIN MARTINBRUBAKER. of hydroxy stearin. v

